System for automatically performing separation or purification of biological materials

ABSTRACT

A system for automatically performing the operations of separating and purifying a variety of biological materials for processing nucleic acids or biological materials from biological samples using solid materials. A base plate, a carriage attachment frame assembly including a frame and a plurality of mounting units, a magnetic bar assembly including a frame, a base plate transport unit, a carriage attachment frame assembly transport unit, a magnetic bar transport unit, and a control unit are utilized. A predetermined number and a small amount of samples can be selectively processed in accordance with a user&#39;s needs.

The present patent application is a Divisional of application Ser. No.10/440,791, filed May 19, 2003.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a system for automatically performingthe operations of separating and purifying a variety of biologicalmaterials.

2. Description of the Prior Art

Machines for separating and purifying nucleic acids or biologicalmaterials from blood or other biological samples have been widely usedin a variety of fields such as biology, biochemistry, molecularmedicine, forensic medicine, medical diagnostics, etc.

Recently, Polymerase Chain Reaction (hereinafter, referred to as “PCR”)for DNA amplification, which became the foundation for the rapiddevelopment of genetic engineering, has been frequently used as anessential step in both biological research and diagnostic fields (SeeU.S. Pat. No. 4,683,195). Conventional methods for isolating nucleicacids generally involve organic solvents such as phenol and chloroform.Further, several methods have been proposed using materials that havethe property of binding nucleic acids. Concrete examples of thesematerials are silica, glass fibers, anion exchange resins and modifiedmagnetic beads.

The methods using these materials have advantages in that no harmfulorganic solvents are involved, that physical and biochemical degradationof nucleic acids during the isolation process is minimized, and thatimmobilized nucleic acids are less susceptible to digestion by nucleicacid-degrading enzymes. The aforementioned methods, however, still needintensive manual pipetting steps to transfer the solid materials toother vessels or containers. Thus, there is a problem in that theoperator is vulnerable to potential viral and bacterial infection ifinfected blood or bacteria is the starting material of nucleic acidisolation.

In order to solve these problems, eliminate experimental errors due tomanual operation and obtain more reliable measurement results, severalautomatic machines such as “MagNa Pure LC” (Roche, Switzerland) weredeveloped to perform a large number of sample manipulations based on theconcept disclosed in U.S. Pat. No. 3,985,649. Most of these automaticmachines utilize magnetic beads to eliminate the use of harmful chemicalsolvents and centrifugation steps when collecting nucleic acids orbiological materials from various biological samples. Although theselarge automatic machines are adequate for high throughput isolation ofthe nucleic acids or biological materials, they are also bulky,expensive, rather complicated, and inefficient for a small or mediumnumber of sample manipulations. As a result, these machines are notpractical for most diagnostic clinical and small research laboratories.

Further, small and medium automatic machines, such as “KingFisher”(Thermo Labsystems, Massachusetts, USA) and SX-6G (PSS, Chiba, Japan),designed for processing a relatively small amount of samples have beenrecently developed. These automatic machines have been designed in sucha manner that a total amount of samples can be processed when performingsample measurement or processing operations, however, there is stillanother problem in that they are not yet efficient for measurement ofonly a predetermined number of samples. That is, there is still a needfor a small and portable automatic machine capable of selectivelyprocessing the necessary number of samples if necessary.

SUMMARY OF THE INVENTION

The present invention is contemplated to solve the problems related withconventional machines for separating nucleic acids or biologicalmaterials from a variety of biological samples according to the priorarts.

An object of the present invention is to provide an automated sampleprocessing system capable of selectively processing the necessary numberof samples.

According to an aspect of the present invention, there is provided asystem for processing nucleic acids or biological materials frombiological samples using a desired number of the kits. The system of thepresent invention comprises a base plate on which the desired number ofcontainers with a series of chambers can be selectively installed inaccordance with a test object; a carriage attachment frame assemblyincluding a frame through which a plurality of holes are formed inaccordance with a predetermined arrangement of the containers installedon the base plate, and a plurality of mounting means which are formed ona bottom surface of the frame correspondingly to the mounting means ofthe carriages such that the carriages of the kits can be selectivelyattached to or detached from the frame in accordance with thepredetermined arrangement; a magnetic bar assembly including a framewith a plurality of magnetic bars attached to a bottom surface of theframe to correspond to the holes formed through the frame of thecarriage attachment frame assembly; a base plate transport unit forhorizontally moving the base plate on which the containers have beenselectively arranged; a carriage attachment frame assembly transportunit for vertically moving the carriage attachment frame assembly to mixor stir buffers and solid materials in the chambers; a magnetic bartransport unit for vertically moving the magnetic bars of the magneticbar assembly through the holes and inside passages of the carriages; anda control unit for controlling the transport units in accordance with apredetermined separation and processing procedure.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other objects and features of the present invention willbecome apparent from the following description of preferred embodimentsgiven in connection with the accompanying drawings, in which:

FIG. 1 is a sectional view of a kit according to the present invention;

FIG. 2 is a plan view illustrating a detailed configuration of acarriage in the kit shown in FIG. 1;

FIG. 3 is a perspective view illustrating the kit shown in FIG. 1 andseveral components of an automation system used with the kit;

FIG. 4 shows the entire configuration of the automation system in whicha given number of kits according to the present invention are installed;

FIG. 5 is a view of a carriage in a kit according to a modifiedembodiment of the present invention; and

FIG. 6 is a view of a carriage in a kit according to another modifiedembodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

Hereinafter, preferred embodiments of the present invention will beexplained in detail with reference to the accompanying drawings.

FIGS. 1 and 2 specifically show a kit for use in separating nucleicacids and biological materials from biologic samples according to thepresent invention.

As shown in FIG. 1, the kit 100 of the present invention comprises arectilinear container 10 including a plurality of chambers 14, and acarriage 20 with a projection 23 configured to be inserted into each ofthe chambers 14 of the container 10. Solid materials and bufferssuitable for the separation of nucleic acids or biological materials arecontained in the respective chambers 14 of the container 10, which arearranged in a row in the container 10. Further, the carriage 20 includesa flat portion 21 with a hole 22 formed therethrough, and a projection23 including an inside passage of which one end is closed and the otherend is open and having a predetermined length so that the blind end canbe dipped into the buffers in the chamber 14. Furthermore, as best shownin FIG. 2, a mounting means 24 is installed on the flat portion 21 ofthe carriage 20 such that the carriage 20 can be detachably mounted to acarriage attachment frame assembly 30 (Refer to FIGS. 3 and 4 to bedescribed later). Such a mounting means 24 may be configured in the formof a general magnet, rubber magnet, neodymium magnet, or magnetic metalbody. Since the mounting means of the carriage can be attached to acomplementary magnet-type mounting means of the carriage attachmentframe assembly 30, the carriage 20 can also be attached to the carriageattachment frame assembly 30. Consequently, the carriage 20 can betransferred in accordance with a predetermined sample processingprocedure.

The chambers 14 of the container 10 have a generally rectangularsectional shape for space efficiency, but need not be limited thereto.For example, the sectional shape may be circular or oval. In addition,the sectional shape of the projection 23 of the carriage 20 need not benecessarily limited thereto, but preferably corresponds to that of thechamber 14.

A plurality of containers 10 of the kit 100 can be selectively mountedto a base plate 50 by the predetermined number necessary for the givenseparation and purification test. Accordingly, the predetermined numberof containers 10 can be moved on a horizontal plane in accordance withthe predetermined procedures by a base plate transport means 80 (referto FIG. 4) to be described later.

As specifically shown in FIG. 2, the mounting means 24 such as magnetsare formed on both sides of a top surface of the flat portion 21 so thatthe carriage 20 can be easily attached to the carriage attachment frameassembly 30. But, the present invention is not necessarily limitedthereto, and may be configured in such a manner that the mounting meansis formed in the interior of the flat portion 21 of the carriage 20. Ofcourse, so far as it may be detachably and stably attached to thecarriage attachment frame assembly 30, any kind of well-known mountingmeans such as Velcro fasteners can be employed in the present invention.

Further, solid materials, buffers, and the like may be filled beforehandinto the respective chambers 14 of the container 10 in accordance with apredetermined procedure so that inexperienced users who are not skillfulin the processing of nucleic acids and biological materials frombiological samples can easily perform the procedure. It is preferredthat the solid materials be magnetic beads for allowing the nucleicacids or biological materials to be easily collected or transferred.

Moreover, it is also preferred that the container 10 and the carriage 20be made of materials such as polycarbonate, polypropylene, polystyrene,and acrylonitrile-butadiene-styrene (ABS) for easy manufacture of thekit and minimization of chemical reaction with the solid materials andbuffers.

A system for automatically separating and purifying the nucleic acidsand biological materials using the aforementioned kit will be nowexplained with reference to FIGS. 3 and 4.

A means, which is used for processing the solid materials in accordancewith the predetermined procedure and transferring the processedmaterials so as to collect and transfer the nucleic acids and biologicalmaterials in the container 10 of the kit 100, is first explained.

FIG. 3 is a perspective view showing a state where the carriageattachment frame assembly 30 and a magnetic bar assembly 40 are usedwith the kit 100. The carriage attachment frame assembly 30 is used toselectively mount the aforementioned carriage 20, and the magnetic barassembly 40 includes magnetic bars 42 for allowing biological materialssuch as nucleic acids to be processed using solid materials such as themagnetic beads in a state where the carriage 20 is attached to themagnetic bar assembly 40.

As shown in FIG. 3, the carriage attachment frame assembly 30 includes aflat portion 36 (hereinafter, referred to as the “lower frame”). Thelower frame 36 is configured in such a manner that each hole 32 isconnected with the hole 22 of the carriage 20 and magnet-type mountingmeans are also formed at positions corresponding to those of the magnets24 of the carriage 20. As explained in connection with the carriage 20,the complementary mounting means of the lower frame may be formed on abottom surface of the lower frame 36 and also be formed in the interiorof the lower frame 36, if necessary. Of course, any other kind ofdetachable mounting means such as described above in connection with thecarriage may be provided instead of using magnets.

In addition, the magnetic bar assembly 40 placed or arranged above thecarriage attachment frame assembly 30 includes a flat portion 46(hereinafter, referred to as the “upper frame”). The magnetic bars 42extending vertically downward by a predetermined length are formed atpositions corresponding to those of the holes 32 of the carriageattachment frame assembly 30 on a bottom surface of the upper frame 46.Each of the magnetic bars 42 is configured to enter the inside passageof the projection 23 of the carriage 20 through the relevant holes 32and 22 of the carriage attachment frame assembly 30 and the carriage 20.As will be described later, it is preferred that the length of eachmagnetic bar 42 be formed somewhat longer than the distance from thebottom surface of flat portion 21 of the carriage 20 to the lowermostend of each projection 23 so that the user can cause the carriage 20 tobe easily detached from the carriage attachment frame assembly 30 ifnecessary.

The automation system will be now explained in detail with reference toFIG. 4. The system 200 comprises a base plate 50 on which thepredetermined number of containers 10 of the kit 100 can be installed inaccordance with a test object, the carriage attachment frame assembly 30for mounting the predetermined number of carriages 20 of the kit 100thereto, the magnetic bar assembly 40, a carriage attachment frametransport unit 60 for moving the carriages 20 and the carriageattachment frame assembly 30 in a vertical direction, a magnetic barassembly transport unit 70 for moving the magnetic bar assembly 40 inthe vertical direction, a base plate transport unit 80 for moving thebase plate 50 in a horizontal direction, and a control device 90 forcontrolling all the transport units.

In general, the carriage attachment frame transport unit 60 causes thecarriage attachment frame assembly 30 to be belt-driven through a firstmotor 65, and the magnetic bar assembly transport unit 70 causes themagnetic bar assembly 40 to be belt-driven through a second motor 75.Further, the base plate transport unit 80 causes the base plate 50 to begear-driven through a third motor (not shown). Of course, any other kindof means such as belts or gears may be employed as a means of transport.

As described above, each of the carriages 20 can be transferred by thecarriage attachment frame transport unit 60 in a state where themounting means 24 installed on the flat portion 21 are attached to thecomplementary mounting means installed on the lower frame 36, and theprojection 23 can be dipped into the relevant chamber of the container10 when the flat portion 21 of the carriage 20 approaches the topsurface of the container 10. When the carriage 20 moves upward anddownward, therefore, the buffers (e.g., liquid reagents) and the solidmaterials can be mixed or stirred effectively in each relevant chamber14 by means of each projection 23. Other means for allowing thecontainer 10 to be shaken may be provided to more effectively agitate ormix the solid materials and the buffers.

Further, in order to collect the solid materials in the relevant chamber14 and then transfer the collected solid materials to the next chamber,each of the magnetic bars 42 of the magnetic bar assembly 40 is insertedthrough the hole 22 and the inside passage of the projection 23 of therelevant carriage 20 to come into contact with a lowermost end wall ofthe projection 23 by means of downward transport movement of themagnetic bar assembly transport unit 70. At this time, it is preferredthat the magnetic bar assembly transport unit 70 be in synchronizationwith the carriage attachment frame transport unit 60, and thus, themagnetic bars 42 of the magnetic bar assembly 40 are moved into thechambers 14 of the container 10 together with the carriages 20. That is,when the flat portions 21 of the carriages 20 come into contact with thetop surface of the container 10 in a state where distal ends of themagnetic bars 42 of the magnetic bar assembly 40 are in contact with theinner lowermost end walls of the projections 23 of the carriages 20, theprojections 23 of carriage 20 are dipped into the buffers in thechambers 14. Therefore, the solid materials in the relevant chamber 14are attracted and attached to an outer surface of the projection 23 bymeans of magnetic force from the magnetic bar 42 so that the solidmaterials such as the magnetic beads can be properly collected. Then,the carriages 20 etc. are raised to a certain extent that the container10 can be moved without interference from the projections 23 of thecarriages 20, and the base plate 50 with the container 10 installedthereon is horizontally moved by a horizontal distance corresponding toa predetermined pitch thereof using the base plate transport unit 80.Subsequently, the carriage attachment frame assembly 30 and the magneticbar assembly 40 are lowered into the next chamber to perform the nextprocess. By repeating the aforementioned process, predeterminedprocedures can be automatically performed by the control unit 90.Therefore, final components such as the nucleic acids or biologicalmaterials can be easily obtained in the final chambers.

A microcomputer may be generally used as the control unit 90 forcontrolling the predetermined procedure and the transport units. Ofcourse, a microchip for performing the same object as the control unitmay also be employed. Since the configuration and operation of thecontrol unit 90 are substantially identical to those of the conventionalcontrol unit, a detailed description thereof will be omitted.

Furthermore, after completion of a portion of the procedure such as theseparation and purification of the nucleic acids or biological materialsor at a proper time the user wants, the carriage 20 should be able to bedetached from the carriage attachment frame assembly 30. As describedabove, in order to cause the carriage 20 to be easily detached from thecarriage attachment frame assembly 30, the longitudinal length of eachof the magnetic bars 42 should be a little greater than the distancefrom the bottom surface of the flat portion 21 of the carriage 20 to thelowermost end of the projection 23. That is, by configuring a controlprogram or performing a manual operation such that the relevant magneticbar 42 of the magnetic bar assembly 40 can be fully inserted into theinside passage of the projection 23 through the hole 32 of the carriageattachment frame assembly 30 and the hole 22 of the carriage 20 at adesired time of period, the magnetic bar 42 is configured to pushagainst the inner lowermost end wall of the projection 23 of thecarriage 20. Thus, since the pushing action can overcome the magneticforce of the magnet-type mounting means, the carriage 20 can beseparated from the carriage attachment frame assembly 30. Accordingly,the kit 100 containing the final components obtained according to thepredetermined procedures can be used in an additional necessary process.

In the meantime, the configuration and shape of the carriage exert agreat influence on the amount of samples and magnetic particles adheringto the surface of the carriage as well as how well the samples can bemixed in the chambers of the container. FIGS. 5 and 6 show otherpreferred embodiments of the carriage of the kit according to thepresent invention, which has been modified for improving the mixing orstirring performance.

As shown in FIGS. 5 and 6, the carriage 20 of the kit 100 according tothe present invention is configured to include a bulged portion 26,which has a sectional area greater than a horizontal sectional area ofthe projection 23, at the lower end of the projection 23. Thus, sincethe bulged portion 26 of the carriage 20 having the horizontal sectionalarea greater than that of the projection 23 enters the chamber 14 of thecontainer 10, a liquid stream flowing around the bulged portion 26becomes stronger, and thus, the liquid can be well mixed or stirred. Inaddition, since a predetermined vortex-forming space is provided behindthe bulged portion 26 of the carriage 20, the mixing process is furtheraccelerated. In order to further improve this mixing effect, two or morebulged portions 26 may be arranged in a row in a longitudinal directionof the carriage 20. Moreover, it is preferred that a bottom surface ofthe bulged portion 26 has a shape exactly corresponding to that of thechamber 14 of the container 10 (e.g., flat, hemispherical, conical, andthe like) such that the liquid can be vigorously mixed and a great dealof the magnetic particles can adhere to the bulged portion 26.

Although it has not yet shown and illustrated in the figures, grooves orprotrusions may be formed on the floor surface of the bulged portion 26of the carriage 20 of the present invention so that the carriage 20cannot be inadvertently detached from the carriage attachment frameassembly 30 due to the adhesion force of the bottom surface of thebulged portion 26 with the liquid residing within the chamber when thecarriage 20 fully enters and retracts from the chamber 14 of thecontainer 10.

In particular, the carriage 20 with the bulged portion 26 constructed assuch can be used with liquid samples and also with solid samples such asplants, insects or animal tissues. That is, since the bulged portion 26is formed to be larger than the carriage projection 23 in a radialdirection of the carriage and to have its bottom surface correspondingto that of the chamber 14, the bulged portion 26 can cause leaves of theplants and the insects to be crushed and pulverized directly in therelevant chamber so that they become biological samples suitable for theisolation of nucleic acids or other biological materials. Thus, samplessuch as plants, insects or animal tissues may be applied directly to thekit of the present invention.

According to the present invention, a predetermined number of the kits,which include the carriage and the container with a plurality ofchambers filled beforehand with buffers, solid materials, enzymes andthe like in accordance with the object of test or experiment, can beselectively installed on the base plate. Thus, the manual operation ofthe user who is not skillful in performing clinical or biological testsor experiments is not required, and a small or medium number of samplescan be very efficiently manipulated.

As a result, the small amount of samples can be quickly processed, andthus, there is an additional advantage in that unnecessary waste ofsamples can be avoided.

Further, the bulged portion is formed at the lower end of the carriagein such a manner that it has a horizontal sectional area greater thanthat of the projection plants or insects and its bottom surfacecorresponds to that of relevant chamber of the container. Thus, thereare advantages in that liquid in the chamber is well mixed when thecarriage enters the chamber and that solid samples such as the plants,insects or animal tissues can be used directly in the kit of the presentinvention.

While the invention has been shown and described with respect to thepreferred embodiments, it will be understood by the skilled in the artthat various changes and modifications may be made thereto withoutdeparting from the spirit and scope of the invention defined by theappended claims. Accordingly, the present invention should be construedas including the inventions defined by the appended claims and theequivalents thereof.

1. A system for processing nucleic acids or biological materials frombiological samples using solid materials, with a desired number of kits,comprising: a base plate on which the desired number of containers witha series of chambers can be selectively installed in accordance with atest object; a carriage attachment frame assembly including a framethrough which a plurality of holes are formed in accordance with apredetermined arrangement of the containers installed on the base plate,and a plurality of mounting means which are formed on a bottom surfaceof the frame correspondingly to the mounting means of the carriages suchthat the carriages of the kits can be selectively attached to ordetached from the frame in accordance with the predeterminedarrangement; a magnetic bar assembly including a frame with a pluralityof magnetic bars attached to a bottom surface of the frame to correspondto the holes formed through the frame of the carriage attachment frameassembly; a base plate transport unit for horizontally moving the baseplate on which the containers have been selectively arranged; a carriageattachment frame assembly transport unit for vertically moving thecarriage attachment frame assembly to mix or stir buffers and biologicalsamples in the chambers; a magnetic bar transport unit for verticallymoving the magnetic bars of the magnetic bar assembly through the holesand inside passages of the carriages; and a control unit for controllingthe transport units in accordance with a predetermined separation andprocessing procedure.
 2. The system as claimed in claim 1, wherein thesolid materials are magnetic beads used for collecting or transferringthe nucleic acids or biological materials.
 3. The system as claimed inclaim 1, wherein the mounting means is a magnet.
 4. The system asclaimed in claim 1, wherein the length of each of the magnetic bars ofthe magnetic bar assembly is greater than a distance from a top surfaceof the frame of the carriage attachment frame assembly to a lowermostend of the inside passage, whereby the carriage can be detached from thecarriage attachment frame assembly.
 5. The system as claimed in claim 1,wherein the carriage attachment frame transport unit and the magneticbar assembly transport unit are driven in synchronization with eachother.
 6. The system as claimed in claim 1, wherein the transport unitsinclude motors and belts or gears.